US6575573B2 - Method and apparatus for measuring a corneal profile of an eye - Google Patents
Method and apparatus for measuring a corneal profile of an eyeDownload PDFInfo
- Publication number
- US6575573B2 US6575573B2US09/981,054US98105401AUS6575573B2US 6575573 B2US6575573 B2US 6575573B2US 98105401 AUS98105401 AUS 98105401AUS 6575573 B2US6575573 B2US 6575573B2
- Authority
- US
- United States
- Prior art keywords
- slit light
- light beam
- corneal
- slit
- placido ring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related, expires
Links
- 238000000034methodMethods0.000titleclaimsabstractdescription25
- 210000004087corneaAnatomy0.000claimsabstractdescription45
- 230000005855radiationEffects0.000claimsabstractdescription28
- 238000001228spectrumMethods0.000claimsdescription11
- 239000013307optical fiberSubstances0.000claimsdescription9
- 238000002329infrared spectrumMethods0.000claimsdescription2
- 238000003745diagnosisMethods0.000claims2
- 238000000926separation methodMethods0.000claims2
- 238000005259measurementMethods0.000abstractdescription8
- 238000012876topographyMethods0.000description12
- 238000005286illuminationMethods0.000description8
- 230000003287optical effectEffects0.000description3
- 230000001360synchronised effectEffects0.000description3
- 238000000429assemblyMethods0.000description2
- 238000010586diagramMethods0.000description2
- 230000002349favourable effectEffects0.000description2
- 230000007246mechanismEffects0.000description2
- 230000000007visual effectEffects0.000description2
- 230000000694effectsEffects0.000description1
- 230000004424eye movementEffects0.000description1
- 239000000835fiberSubstances0.000description1
- 238000003384imaging methodMethods0.000description1
- 238000001454recorded imageMethods0.000description1
- 238000001356surgical procedureMethods0.000description1
Images
Classifications
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B3/00—Apparatus for testing the eyes; Instruments for examining the eyes
- A61B3/10—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
- A61B3/107—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions for determining the shape or measuring the curvature of the cornea
Definitions
- the present inventionpertains to method and apparatus for measuring a corneal profile of an eye.
- the present inventionrelates to method and apparatus for measuring a corneal topography and a corneal thickness profile of an eye.
- the corneal topographyi.e., a curvature profile of an anterior surface of a cornea
- the corneal topographycan be provided by a corneal topographer.
- the corneal thickness profilecan be observed and analyzed. Further, if the projection angle and the viewing angle of the slit light beam are predetermined, and the corneal topography is measured, the corneal thickness profile of the cornea can be calculated from the measured width of the cross section of the intersection of the slit light beam on the cornea.
- slit light beam imagesare recorded by a video camera, and the recorded images are processed in a digital format to produce a corneal curvature profile (the corneal topography) and a corneal thickness profile.
- slit light beamsare projected from two sides of an instrument axis, and slit light beam images are taken along the instrument axis.
- the slit light beamsare scanned across the cornea in a parallel direction, and a video image is taken at each step of the slit light beam scan positions.
- a video imageis taken at each step of the slit light beam scan positions.
- the corneal topographyto be measured at a large number of points across the anterior surface of the cornea.
- a large number of slit light beam imagesis required to generate sufficient data to measure accurately the corneal topography and the corneal thickness profile.
- a commercial instrument based on the disclosed design principletakes some forty (40) images for each measurement, and as a result, the data acquisition process takes a few seconds to complete.
- one embodiment of the present inventionis a corneal diagnostic instrument that obtains a corneal topography and a corneal thickness profile.
- one embodiment of the present inventioncomprises: (a) a Placido ring illuminator disposed to project radiation onto a cornea to generate a Placido ring image; (b) multiple slit lamp projectors disposed to project slit light beams onto the cornea to generate slit light beam images; (c) a camera system optically disposed to detect the Placido ring image and the slit light beam images; and (d) a controller, coupled to the slit lamp projectors, the Placido ring illuminator, and the camera system, to cause the slit light beam images and the Placido ring image to be generated and detected in a predetermined sequence, wherein the controller is responsive to the detected Placido ring image and the detected slit light beam images to determine
- a corneal diagnostic instrumentthat comprises: (a) a corneal topographer that determines a curvature profile of an anterior surface of a cornea; (b) multiple slit lamp projectors disposed to project slit light beams onto the cornea to generate slit light beam images; (c) a camera system optically disposed to detect the slit light beam images; and (d) a controller, coupled to the slit lamp projectors, the corneal topographer, and the camera system, to cause, in a predetermined sequence, (i) the slit light beam images to be generated and detected, and (ii) the corneal topographer to obtain data used to determine the curvature profile, wherein the controller is responsive to the detected slit light beam images and the curvature profile to determine a corneal thickness profile.
- FIG. 1is a schematic diagram of a corneal diagnostic instrument that is fabricated in accordance with one embodiment of the present invention
- FIG. 2is a pictorial representation of a Placido ring image obtained using the corneal diagnostic instrument shown in FIG. 1;
- FIGS. 3 a - 3 dare pictorial representations of four (4) slit light beam images obtained utilizing slit light beams projected from different clocking angles onto a cornea of an eye in accordance with one embodiment of the present invention.
- FIG. 1is a schematic diagram of corneal diagnostic instrument 100 that is fabricated in accordance with one embodiment of the present invention.
- corneal diagnostic instrument 100includes Placido ring illuminator 20 , camera system 40 , a slit lamp projector assembly, synchronizer 35 , and controller 50 .
- the slit lamp projector assemblycomprises a number of slit lamp projector sub-assemblies, but only slit lamp projector sub-assembly 30 i is shown in FIG. 1 to make the embodiment more readily understandable, and not to obscure further details thereof.
- Placido ring illuminator 20comprises face plate 21 that is masked with Placido rings, diffuser plate 22 , and illumination source 23 .
- Face plate 21determines a number and size of Placido rings in the Placido ring image
- diffuser plate 22homogenizes radiation output from illumination source 23 .
- Illumination source 23can be operated to output radiation, for example and without limitation, in the visible or in the near infrared spectrum.
- Face plate 21 , diffuser plate 22 , and illumination source 23may be fabricated in accordance with any one of a number of methods that are well known to those of ordinary skill in the art.
- the Placido ring image generated by use of Placido ring illuminator 20is detected by camera system 40 , and the detected Placido ring image output from camera system 40 is analyzed by controller 50 in accordance with any one of a number of methods that are well known to those of ordinary skill in the art to produce a corneal curvature profile of an anterior surface (i.e., a corneal topography) of cornea 11 .
- controller 50is embodied as a computer, for example, a personal computer.
- synchronizer 35applies a signal to Placido ring illuminator 20 , for example, to illumination source 23 , to cause it to output radiation that generates the Placido ring image at a predetermined time.
- Synchronizer 35may be fabricated in accordance with any one of a number of methods that are well known to those of ordinary skill in the art. In the embodiment shown in FIG. 1, synchronizer 35 receives a signal from controller 50 that causes synchronizer 35 to generate the appropriate signal it sends to illuminator 23 of Placido ring generator 20 . Additionally, synchronizer 35 sends a signal to camera system 40 to cause it to operate to detect the Placido ring image generated by radiation output from Placido ring illuminator 20 which was reflected by cornea 11 . It should be understood that although synchronizer 35 may be embodied as being separate from controller 50 , further embodiments of the present invention exist wherein synchronizer 35 may form a portion of controller 50 .
- Placido ring illuminator 20is turned on for generating the Placido ring image, and it may be turned on for eye alignment. When it is turned on, Placido ring illuminator 20 illuminates eye 10 , and a Placido ring image is reflected by cornea 11 and is imaged on camera system 40 . As shown in FIG. 1, camera system 40 is positioned to view cornea 11 along instrument axis 41 . Instrument axis 41 is aligned with a visual axis of eye 10 in accordance with any one of a number of methods and mechanisms that are well known to those of ordinary skill in the art (such mechanisms are not shown for clarity and ease of understanding the principles of the present invention).
- camera system 40is shown to be physically disposed along instrument axis 41 , it should be appreciated that camera system 40 may be aligned at other positions.
- optical systemswhich are well known to those of ordinary skill in the art (for example and without limitation, beam splitting systems) may be used to ensure that camera system 40 records images as if it were disposed as shown in FIG. 1, i.e., in such a case it may be said to be optically disposed along instrument axis 41 .
- each Placido ringcarries position and curvature information of cornea 11 at the corresponding position.
- the Placido ring image generated by use of Placido ring illuminator 20is detected by camera system 40 , and is analyzed by controller 50 in accordance with any one of a number of methods that are well known to those of ordinary skill in the art to produce a corneal curvature profile of an anterior surface of cornea 11 .
- FIG. 2is a pictorial representation of Placido ring image 14 obtained using corneal diagnostic instrument 100 . In particular, FIG. 2 shows how Placido ring image 14 appears relative to other landmarks of eye 10 .
- the Placido ringsare typically: (a) centered with a vertex of cornea 11 ; and (b) in alignment with, and located within, limbus 13 of eye 10 .
- all the Placido rings in Placido ring image 14will be concentric circles.
- the Placido ringswill bend and curve, depending on the local elevation and curvature of cornea 11 .
- slit lamp projector sub-assembly 30 icomprises radiation source 33 i , optical fiber 32 i , and slit light projector 31 i .
- Optical fiber 32 idelivers radiation output from radiation source 33 i to slit lamp projector 31 i .
- slit light projector sub-assembly 30 iis shown to comprise optical fiber 32 i , further embodiments of the present invention are not so configured, and can be fabricated without using an optical fiber to deliver radiation output from radiation source 33 i to slit light projector 31 i.
- each slit lamp projector 31 iincludes a slit and imaging optics that images the slit onto cornea 11 .
- Slit light beam 34 i output from slit light projector 31 ihas a typical width of about 50 to about 100 microns and a typical length about 8 to about 10 mm on cornea 11 .
- the slit widthis about 10 microns and its length is about 2 mm
- slit light beam 34 ihas a width of about 50 microns and a length of about 10 mm on cornea 11 .
- Many methodsare well known to those of ordinary skill in the art for fabricating the slit and the image optics of slit light projector sub-assemblies 30 i.
- Radiation source 33 ican comprise a flash lamp or a CW lamp.
- each radiation source 33 icomprises a flash lamp that is synchronized with camera system 40 (in response to signals from synchronizer 35 ) for emission of radiation and for capture of images at predetermined times, respectively.
- radiation source 33 icomprises a CW lamp and an optical shutter (not shown).
- the optical shutteris synchronized with camera system 40 (in response to signals from synchronizer 35 ) for passing radiation at a predetermined time for a predetermined time period and for capture of images at predetermined times, respectively.
- synchronizer 35receives a signal from controller 50 that causes synchronizer 35 to generate the appropriate signal it sends to each radiation source 33 i and camera system 40 . It should be understood that although synchronizer 35 may be embodied as being separate from controller 50 , further embodiments of the present invention exist wherein synchronizer 35 may form a portion of controller 50 .
- optical fiber 32 ican be a large core, plastic fiber.
- the core size of optical fiber 32 iis 2 mm.
- use of optical fiber 32 ienables slit-light projector 31 i to be separated from radiation source 33 i . This is advantageous because it is easy to install and align slit light projector 31 i , and to replace a lamp included in radiation source 33 i.
- slit light projectors 31 iare installed around a circle in a plane that intersects face plate 21 and that is substantially perpendicular to instrument axis 41 .
- the present inventionis not thusly limited, and includes embodiments wherein the slit light projectors are not all in a plane or in a circle in a plane.
- slit light projectors 31 iare installed such that each slit-light beam 34 i has substantially the same projection angle on cornea 11 , i.e., the same intersection angle with respect to instrument axis 41 .
- each slit light beam 34 iis aligned such that it intersects instrument axis 41 at approximately 45 degrees, and such that it intersects cornea 11 substantially at its center.
- the present inventionis not thusly limited, and includes embodiments wherein the projection angles of at some or all of the slight light beams are different.
- the number of slit light beams 34 iis 4 to 8, which number of slit light beams 34 i can produce sufficient data and spatial resolution to produce an accurate corneal thickness profile.
- an angular spacing between slit-light beams 34 iis uniform on a corneal plane, for example, a 45 degree angular spacing for an embodiment having 4 slit light beams 34 i and a 22.5 degree angular spacing for an embodiment having 8 slit light beams, the angular spacing being referred to as clocking angles.
- clocking anglesThis is understood as follows.
- Each slit light beam intersects the corneais appears as an image across the cornea. Therefore, four (4) slit light beams divide the cornea into 8 sections, and each section occupies a clocking angle of 45 degrees.
- slit-light beams 34 ican be almost any wavelength, but is preferably in the visible or near infrared. Although scattering from corneal tissue is stronger for shorter wavelengths, ultra-violet is less favorable due to its potential for causing damage to the eye.
- White lightis commonly used in slit lamp examinations, and provides an acceptable choice for use in fabricating embodiments of the present invention. Near infrared radiation also provides an acceptable good choice, and it is less disturbing to subject eye 10 than white light.
- camera system 40is a CCD camera, and in another embodiment, camera system 40 is a video camera.
- the Placido ring image produced by use of Placido ring illuminator 20 and the slit light beam images produced by use of the slit lamp projector assemblyare located on slightly different planes.
- a camera systemthat comprises one camera to record the Placido ring image, and another camera to record the slit light beam images.
- camera system 40may further comprise a beam splitter (it can be installed in front of camera system 40 as shown in FIG. 1) to introduce a beam path for a second camera.
- camera system 40may include a movable lens (it can be installed in front of camera system 40 as shown in FIG. 1) to adjust the image plane in a predetermined manner.
- a movable lensit can be installed in front of camera system 40 as shown in FIG. 1 to adjust the image plane in a predetermined manner.
- the lensmay be moved by a linear motor in response to signals from controller 50 .
- the spectrum of the illumination beam used to generate the Placido ring imagecan be chosen to be different from the spectrum of the illumination beams used to generate the slit light beam images.
- the image beam path for a first cameracan be separated from that for a second camera by a dichromatic beam splitter.
- the Placido ring imagecan be captured at substantially the same time as any one of the slit light beam images is captured.
- the spectra of the illumination beams used to generate the slit imagescan be chosen so that the spectra are different from one another, or the spectra of predetermined ones are different from other predetermined ones.
- images having different spectracan be captured in different cameras of a camera system wherein the image beam paths for the different cameras are separated using beam splitters and filters in accordance with any one of a number of methods that are well known to those of ordinary skill in the art. Lastly, the image beams having different spectra can be detected at the same time.
- FIGS. 3 a - 3 dare pictorial representations of four (4) slit light beam images obtained utilizing slit light beams projected from different clocking angles onto cornea 11 .
- FIG. 3 ashows slit light beam image 16 (at a viewing angle approximately along an axis of eye 10 ) that is formed when a slit light beam intersects eye 10 approximately at a center of cornea 11 .
- the slit light beamis projected: (a) from a position to the right of eye 10 ; and (b) towards eye 10 at a predetermined angle (for example, an angle of approximately 45 degrees) with respect to the visual axis of eye 10 .
- a width of slit light beam image 16is proportional to a corneal thickness, provided the width of the slit light beam is known, and provided that the width is much thinner than the corneal thickness.
- the viewing angle at which the image was taken, and the projection angle of the slit light beamare predetermined.
- a local curvature of cornea 11 at every image point along slit light image 16must be determined to enable ray tracing, through refraction, on an anterior surface of cornea 11 .
- the principles involved in, and algorithms for using, ray tracing to determine corneal thicknessare well known to those of ordinary skill in the art. For example, one can refer to U.S. Pat. Nos.
- FIGS. 3 b - 3 dshow slit light beam images 17 - 19 , respectively, (at a viewing angle approximately along an axis of eye 10 ) that are formed when slit light beams intersect eye 10 approximately at the center of cornea 11 .
- the slit light beamis projected: (a) from a position to the right and above eye 10 ; and (b) towards eye 10 at a predetermined angle (for example, an angle of approximately 45 degrees) with respect to the axis of eye 10 .
- a predetermined anglefor example, an angle of approximately 45 degrees
- the slit light beamis projected: (a) from a position above eye 10 ; and (b) towards eye 10 at an angle of approximately 45 degrees with respect to the axis of eye 10 .
- the slit light beam image 19 of FIG. 3 dthe slit light beam is projected: (a) from a position to the left and above eye 10 ; and (b) towards eye 10 at a predetermined angle (for example, an angle of approximately 45 degrees) with respect to the axis of eye 10 .
- Placido ring illuminator 20 and each slit lamp projector sub-assembly 30 iare turned on, one at a time in a predetermined sequence, which predetermined sequence is synchronized with camera system 40 , to generate a Placido ring image and a plurality of slit light beam images.
- These slit light beam imagescan then be used by controller 50 , in combination with the corneal curvature profile of the anterior surface of cornea 11 generated by analyzing the Placido ring image, to generate a corneal thickness profile.
- An algorithm for use in generating the corneal thickness profilemay be based on triangular ray tracing, and a number of such algorithms are well known to those of ordinary skill in the art.
- corneal diagnostic instrument 100comprises Placido ring illuminator 20 (as shown in FIG. 1 )
- thiscan significantly reduce the data acquisition time when compared with the data acquisition time for designs disclosed in U.S. Pat. Nos. 5,512,965 and 5,512,966.
- Thisis because, for example, use of Placido ring illuminator 20 can generate a great deal of data points at high spatial resolution in a single image. This is advantageous for the additional reason that, since all the data points for measuring the corneal curvature profile are recorded in a single image, eye movement plays no effect on the precision of the measurement.
- the required number of data points and the required spatial resolution of the corneal curvature profile of the corneal anterior surfaceare much greater than that required to measure a corneal thickness profile.
- an accurate measurement of the corneal thickness profile(along one cross section) can be obtained regardless of the number of slit light beam images used.
- An additional advantage of this inventionis the use of multiple slit light projectors to eliminate mechanical movement of a scanning slit light beam, and thus to further reduce data acquisition time and to minimize position error due to mechanical movement.
- FIG. 1shows an embodiment wherein the Placido ring image and the slit light beam images are obtained using the same camera and are analyzed in the same controller
- FIG. 1shows an embodiment wherein the Placido ring image and the slit light beam images are obtained using the same camera and are analyzed in the same controller
- the Placido ring image and the slit light beam imagesare captured in separate cameras, and are analyzed in separate controllers.
- the corneal diagnostic instrumentwould comprise a corneal topographer that generates a corneal topography.
- the predetermined sequencemay include generating and detecting the Placido ring image before generating and detecting the slit light beam images, or vice versa, or some other sequence.
- sequenceis not restricted to a meaning of one thing after another, but is used in a more general sense. That is, the term sequence can include events where things happen at the same time, or where some things happen at the same time and others things happen one after another.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Medical Informatics (AREA)
- Biophysics (AREA)
- Ophthalmology & Optometry (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Physics & Mathematics (AREA)
- Molecular Biology (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Eye Examination Apparatus (AREA)
Abstract
Description
The present invention pertains to method and apparatus for measuring a corneal profile of an eye. In particular, the present invention relates to method and apparatus for measuring a corneal topography and a corneal thickness profile of an eye.
Accurate measurement of a corneal topography and a corneal thickness profile is important for the safety and effectiveness of corneal refractive surgery. As is well known, the corneal topography, i.e., a curvature profile of an anterior surface of a cornea, can be provided by a corneal topographer. Further, it is also well known how to use ray-tracing algorithms to combine slit light beam images and the corneal topography to measure the corneal thickness profile.
For example, whenever a slit light beam is projected onto the cornea, and a cross section of the slit light beam on the cornea is viewed from an angle, the corneal thickness profile can be observed and analyzed. Further, if the projection angle and the viewing angle of the slit light beam are predetermined, and the corneal topography is measured, the corneal thickness profile of the cornea can be calculated from the measured width of the cross section of the intersection of the slit light beam on the cornea.
As disclosed in U.S. Pat. Nos. 5,512,965 and 5,512,966, slit light beam images are recorded by a video camera, and the recorded images are processed in a digital format to produce a corneal curvature profile (the corneal topography) and a corneal thickness profile. As disclosed, slit light beams are projected from two sides of an instrument axis, and slit light beam images are taken along the instrument axis. During the disclosed measurement procedure, the slit light beams are scanned across the cornea in a parallel direction, and a video image is taken at each step of the slit light beam scan positions. To obtain an accurate measurement of the corneal thickness profile, one needs an accurate measurement of the corneal topography with high spatial resolution. This, in turn, requires the corneal topography to be measured at a large number of points across the anterior surface of the cornea. Thus, as disclosed, a large number of slit light beam images is required to generate sufficient data to measure accurately the corneal topography and the corneal thickness profile. In practice, a commercial instrument based on the disclosed design principle takes some forty (40) images for each measurement, and as a result, the data acquisition process takes a few seconds to complete.
In light of the above, there is a need in the art for method and apparatus for measuring corneal profiles of an eye that can operate quickly.
One or more embodiments of the present invention advantageously satisfy the above-identified need in the art. Specifically, one embodiment of the present invention is a corneal diagnostic instrument that obtains a corneal topography and a corneal thickness profile. In particular, one embodiment of the present invention comprises: (a) a Placido ring illuminator disposed to project radiation onto a cornea to generate a Placido ring image; (b) multiple slit lamp projectors disposed to project slit light beams onto the cornea to generate slit light beam images; (c) a camera system optically disposed to detect the Placido ring image and the slit light beam images; and (d) a controller, coupled to the slit lamp projectors, the Placido ring illuminator, and the camera system, to cause the slit light beam images and the Placido ring image to be generated and detected in a predetermined sequence, wherein the controller is responsive to the detected Placido ring image and the detected slit light beam images to determine a corneal thickness profile.
Another embodiment of the present invention is a corneal diagnostic instrument that comprises: (a) a corneal topographer that determines a curvature profile of an anterior surface of a cornea; (b) multiple slit lamp projectors disposed to project slit light beams onto the cornea to generate slit light beam images; (c) a camera system optically disposed to detect the slit light beam images; and (d) a controller, coupled to the slit lamp projectors, the corneal topographer, and the camera system, to cause, in a predetermined sequence, (i) the slit light beam images to be generated and detected, and (ii) the corneal topographer to obtain data used to determine the curvature profile, wherein the controller is responsive to the detected slit light beam images and the curvature profile to determine a corneal thickness profile.
FIG. 1 is a schematic diagram of a corneal diagnostic instrument that is fabricated in accordance with one embodiment of the present invention;
FIG. 2 is a pictorial representation of a Placido ring image obtained using the corneal diagnostic instrument shown in FIG. 1; and
FIGS. 3a-3dare pictorial representations of four (4) slit light beam images obtained utilizing slit light beams projected from different clocking angles onto a cornea of an eye in accordance with one embodiment of the present invention.
FIG. 1 is a schematic diagram of cornealdiagnostic instrument 100 that is fabricated in accordance with one embodiment of the present invention. As shown in FIG. 1, cornealdiagnostic instrument 100 includes Placidoring illuminator 20,camera system 40, a slit lamp projector assembly,synchronizer 35, andcontroller 50. In accordance with this embodiment of the present invention, the slit lamp projector assembly comprises a number of slit lamp projector sub-assemblies, but only slitlamp projector sub-assembly 30iis shown in FIG. 1 to make the embodiment more readily understandable, and not to obscure further details thereof.
In accordance with this embodiment of the present invention, radiation output from Placidoring illuminator 20 is reflected bycornea 11 ofsubject eye 10 to form a Placido ring image that is detected bycamera system 40. In one such embodiment shown in FIG. 1, Placidoring illuminator 20 comprisesface plate 21 that is masked with Placido rings,diffuser plate 22, andillumination source 23.Face plate 21 determines a number and size of Placido rings in the Placido ring image, anddiffuser plate 22 homogenizes radiation output fromillumination source 23.Illumination source 23 can be operated to output radiation, for example and without limitation, in the visible or in the near infrared spectrum. Although visible light is more commonly used, near infrared radiation may be more favorable as it is less disturbing tosubject eye 10.Face plate 21,diffuser plate 22, andillumination source 23 may be fabricated in accordance with any one of a number of methods that are well known to those of ordinary skill in the art.
The Placido ring image generated by use of Placidoring illuminator 20 is detected bycamera system 40, and the detected Placido ring image output fromcamera system 40 is analyzed bycontroller 50 in accordance with any one of a number of methods that are well known to those of ordinary skill in the art to produce a corneal curvature profile of an anterior surface (i.e., a corneal topography) ofcornea 11. In one embodiment,controller 50 is embodied as a computer, for example, a personal computer. Lastly, as shown in FIG. 1,synchronizer 35 applies a signal to Placidoring illuminator 20, for example, toillumination source 23, to cause it to output radiation that generates the Placido ring image at a predetermined time. Synchronizer35 may be fabricated in accordance with any one of a number of methods that are well known to those of ordinary skill in the art. In the embodiment shown in FIG. 1,synchronizer 35 receives a signal fromcontroller 50 that causessynchronizer 35 to generate the appropriate signal it sends toilluminator 23 of Placidoring generator 20. Additionally,synchronizer 35 sends a signal tocamera system 40 to cause it to operate to detect the Placido ring image generated by radiation output from Placidoring illuminator 20 which was reflected bycornea 11. It should be understood that althoughsynchronizer 35 may be embodied as being separate fromcontroller 50, further embodiments of the present invention exist whereinsynchronizer 35 may form a portion ofcontroller 50.
In accordance with one embodiment of the present invention, Placidoring illuminator 20 is turned on for generating the Placido ring image, and it may be turned on for eye alignment. When it is turned on, Placidoring illuminator 20 illuminateseye 10, and a Placido ring image is reflected bycornea 11 and is imaged oncamera system 40. As shown in FIG. 1,camera system 40 is positioned to viewcornea 11 alonginstrument axis 41.Instrument axis 41 is aligned with a visual axis ofeye 10 in accordance with any one of a number of methods and mechanisms that are well known to those of ordinary skill in the art (such mechanisms are not shown for clarity and ease of understanding the principles of the present invention). Althoughcamera system 40 is shown to be physically disposed alonginstrument axis 41, it should be appreciated thatcamera system 40 may be aligned at other positions. In that case, optical systems which are well known to those of ordinary skill in the art (for example and without limitation, beam splitting systems) may be used to ensure thatcamera system 40 records images as if it were disposed as shown in FIG. 1, i.e., in such a case it may be said to be optically disposed alonginstrument axis 41.
As is well known, the shape and size of each Placido ring carries position and curvature information ofcornea 11 at the corresponding position. The Placido ring image generated by use of Placidoring illuminator 20 is detected bycamera system 40, and is analyzed bycontroller 50 in accordance with any one of a number of methods that are well known to those of ordinary skill in the art to produce a corneal curvature profile of an anterior surface ofcornea 11. FIG. 2 is a pictorial representation of Placidoring image 14 obtained using cornealdiagnostic instrument 100. In particular, FIG. 2 shows how Placidoring image 14 appears relative to other landmarks ofeye 10. For example, the Placido rings are typically: (a) centered with a vertex ofcornea 11; and (b) in alignment with, and located within,limbus 13 ofeye 10. For a perfectly spherical corneal surface, all the Placido rings in Placidoring image 14 will be concentric circles. However, whenevercornea 11 deviates from a perfectly spherical surface, the Placido rings will bend and curve, depending on the local elevation and curvature ofcornea 11.
As shown in FIG. 1, slitlamp projector sub-assembly 30icomprisesradiation source 33i,optical fiber 32i, andslit light projector 31i.Optical fiber 32idelivers radiation output fromradiation source 33ito slitlamp projector 31i. Although slitlight projector sub-assembly 30iis shown to compriseoptical fiber 32i, further embodiments of the present invention are not so configured, and can be fabricated without using an optical fiber to deliver radiation output fromradiation source 33ito slitlight projector 31i.
In accordance with one embodiment of the present invention, eachslit lamp projector 31iincludes a slit and imaging optics that images the slit ontocornea 11.Slit light beam 34ioutput fromslit light projector 31ihas a typical width of about 50 to about 100 microns and a typical length about 8 to about 10 mm oncornea 11. In one such embodiment, the slit width is about 10 microns and its length is about 2 mm, and slitlight beam 34ihas a width of about 50 microns and a length of about 10 mm oncornea 11. Many methods are well known to those of ordinary skill in the art for fabricating the slit and the image optics of slitlight projector sub-assemblies 30i.
For the embodiment shown in FIG. 1,optical fiber 32ican be a large core, plastic fiber. In one such embodiment, the core size ofoptical fiber 32iis 2 mm. In accordance with the embodiment of the present invention shown in FIG. 1, use ofoptical fiber 32ienables slit-light projector 31ito be separated fromradiation source 33i. This is advantageous because it is easy to install and align slitlight projector 31i, and to replace a lamp included inradiation source 33i.
In accordance with one embodiment of the present invention, slitlight projectors 31iare installed around a circle in a plane that intersectsface plate 21 and that is substantially perpendicular toinstrument axis 41. However, the present invention is not thusly limited, and includes embodiments wherein the slit light projectors are not all in a plane or in a circle in a plane. In accordance with one such embodiment, slitlight projectors 31iare installed such that each slit-light beam 34ihas substantially the same projection angle oncornea 11, i.e., the same intersection angle with respect toinstrument axis 41. In one such embodiment, each slitlight beam 34iis aligned such that it intersectsinstrument axis 41 at approximately 45 degrees, and such that it intersectscornea 11 substantially at its center. However, the present invention is not thusly limited, and includes embodiments wherein the projection angles of at some or all of the slight light beams are different.
In one embodiment of the present invention, the number of slit light beams34iis 4 to 8, which number of slit light beams34ican produce sufficient data and spatial resolution to produce an accurate corneal thickness profile. In such an embodiment, an angular spacing between slit-light beams 34iis uniform on a corneal plane, for example, a 45 degree angular spacing for an embodiment having 4 slit light beams34iand a 22.5 degree angular spacing for an embodiment having 8 slit light beams, the angular spacing being referred to as clocking angles. This is understood as follows. Each slit light beam intersects the cornea is appears as an image across the cornea. Therefore, four (4) slit light beams divide the cornea into 8 sections, and each section occupies a clocking angle of 45 degrees.
The spectrum of slit-light beams 34ican be almost any wavelength, but is preferably in the visible or near infrared. Although scattering from corneal tissue is stronger for shorter wavelengths, ultra-violet is less favorable due to its potential for causing damage to the eye. White light is commonly used in slit lamp examinations, and provides an acceptable choice for use in fabricating embodiments of the present invention. Near infrared radiation also provides an acceptable good choice, and it is less disturbing tosubject eye 10 than white light.
In accordance with one embodiment of the present invention,camera system 40 is a CCD camera, and in another embodiment,camera system 40 is a video camera. In practice, the Placido ring image produced by use ofPlacido ring illuminator 20 and the slit light beam images produced by use of the slit lamp projector assembly are located on slightly different planes. To obtain the best quality images, one may use a camera system that comprises one camera to record the Placido ring image, and another camera to record the slit light beam images. For example, to do this,camera system 40 may further comprise a beam splitter (it can be installed in front ofcamera system 40 as shown in FIG. 1) to introduce a beam path for a second camera. Alternatively, one can adjust the focal plane ofcamera system 40 between times of obtaining the Placido ring image and the slit light beam images. To do this,camera system 40 may include a movable lens (it can be installed in front ofcamera system 40 as shown in FIG. 1) to adjust the image plane in a predetermined manner. Many methods are well known to those of ordinary skill in the art for fabricating a moving a lens. In some such embodiment, the lens may be moved by a linear motor in response to signals fromcontroller 50.
When a camera system comprised of two cameras is used, the spectrum of the illumination beam used to generate the Placido ring image can be chosen to be different from the spectrum of the illumination beams used to generate the slit light beam images. Thus, the image beam path for a first camera can be separated from that for a second camera by a dichromatic beam splitter. In this way, the Placido ring image can be captured at substantially the same time as any one of the slit light beam images is captured. In addition, in a further embodiment, the spectra of the illumination beams used to generate the slit images can be chosen so that the spectra are different from one another, or the spectra of predetermined ones are different from other predetermined ones. Then, images having different spectra can be captured in different cameras of a camera system wherein the image beam paths for the different cameras are separated using beam splitters and filters in accordance with any one of a number of methods that are well known to those of ordinary skill in the art. Lastly, the image beams having different spectra can be detected at the same time.
FIGS. 3a-3dare pictorial representations of four (4) slit light beam images obtained utilizing slit light beams projected from different clocking angles ontocornea 11. FIG. 3ashows slit light beam image16 (at a viewing angle approximately along an axis of eye10) that is formed when a slit light beam intersectseye 10 approximately at a center ofcornea 11. To form slitlight beam image 16 of FIG. 3a, the slit light beam is projected: (a) from a position to the right ofeye 10; and (b) towardseye 10 at a predetermined angle (for example, an angle of approximately 45 degrees) with respect to the visual axis ofeye 10. As is well known, a width of slitlight beam image 16 is proportional to a corneal thickness, provided the width of the slit light beam is known, and provided that the width is much thinner than the corneal thickness. To calculate the corneal thickness from slitlight beam image 16, the viewing angle at which the image was taken, and the projection angle of the slit light beam are predetermined. Also a local curvature ofcornea 11 at every image point along slitlight image 16 must be determined to enable ray tracing, through refraction, on an anterior surface ofcornea 11. The principles involved in, and algorithms for using, ray tracing to determine corneal thickness are well known to those of ordinary skill in the art. For example, one can refer to U.S. Pat. Nos. 5,512,965 and 5,512,966. Similarly, FIGS. 3b-3dshow slit light beam images17-19, respectively, (at a viewing angle approximately along an axis of eye10) that are formed when slit light beams intersecteye 10 approximately at the center ofcornea 11. To form slitlight beam image 17 of FIG. 3b, the slit light beam is projected: (a) from a position to the right and aboveeye 10; and (b) towardseye 10 at a predetermined angle (for example, an angle of approximately 45 degrees) with respect to the axis ofeye 10. To form slitlight beam image 18 of FIG. 3c, the slit light beam is projected: (a) from a position aboveeye 10; and (b) towardseye 10 at an angle of approximately 45 degrees with respect to the axis ofeye 10. To form slitlight beam image 19 of FIG. 3d, the slit light beam is projected: (a) from a position to the left and aboveeye 10; and (b) towardseye 10 at a predetermined angle (for example, an angle of approximately 45 degrees) with respect to the axis ofeye 10.
In operation, in accordance with one embodiment of the present invention,Placido ring illuminator 20 and each slitlamp projector sub-assembly 30i, for example, slitlight projectors 31ithereof, are turned on, one at a time in a predetermined sequence, which predetermined sequence is synchronized withcamera system 40, to generate a Placido ring image and a plurality of slit light beam images. These slit light beam images can then be used bycontroller 50, in combination with the corneal curvature profile of the anterior surface ofcornea 11 generated by analyzing the Placido ring image, to generate a corneal thickness profile. An algorithm for use in generating the corneal thickness profile may be based on triangular ray tracing, and a number of such algorithms are well known to those of ordinary skill in the art.
Advantageously, in accordance with one or more embodiments of the present invention, when cornealdiagnostic instrument 100 comprises Placido ring illuminator20 (as shown in FIG.1), this can significantly reduce the data acquisition time when compared with the data acquisition time for designs disclosed in U.S. Pat. Nos. 5,512,965 and 5,512,966. This is because, for example, use ofPlacido ring illuminator 20 can generate a great deal of data points at high spatial resolution in a single image. This is advantageous for the additional reason that, since all the data points for measuring the corneal curvature profile are recorded in a single image, eye movement plays no effect on the precision of the measurement.
Further, in practice, the required number of data points and the required spatial resolution of the corneal curvature profile of the corneal anterior surface are much greater than that required to measure a corneal thickness profile. Thus, once a precise corneal curvature profile is obtained, an accurate measurement of the corneal thickness profile (along one cross section) can be obtained regardless of the number of slit light beam images used.
An additional advantage of this invention is the use of multiple slit light projectors to eliminate mechanical movement of a scanning slit light beam, and thus to further reduce data acquisition time and to minimize position error due to mechanical movement.
Those skilled in the art will recognize that the foregoing description has been presented for the sake of illustration and description only. As such, it is not intended to be exhaustive or to limit the invention to the precise form disclosed. For example, although FIG. 1 shows an embodiment wherein the Placido ring image and the slit light beam images are obtained using the same camera and are analyzed in the same controller, further embodiments of the present invention exist wherein the Placido ring image and the slit light beam images are captured in separate cameras, and are analyzed in separate controllers. For example, in one such embodiment, the corneal diagnostic instrument would comprise a corneal topographer that generates a corneal topography. In addition, in some embodiments, the predetermined sequence may include generating and detecting the Placido ring image before generating and detecting the slit light beam images, or vice versa, or some other sequence. Note that the term sequence is not restricted to a meaning of one thing after another, but is used in a more general sense. That is, the term sequence can include events where things happen at the same time, or where some things happen at the same time and others things happen one after another.
Claims (27)
1. A corneal diagnostic instrument that comprises:
a Placido ring illuminator disposed to project radiation onto a cornea to generate a Placido ring image;
multiple slit lamp projectors disposed to project slit light beams onto the cornea to generate slit light beam images;
a camera system optically disposed to detect the Placido ring image and the slit light beam images; and
a controller, coupled to the slit lamp projectors, the Placido ring illuminator, and the camera system, to cause the slit light beam images and the Placido ring image to be generated and detected in a predetermined sequence, wherein the controller is responsive to the detected Placido ring image and the detected slit light beam images to determine a corneal thickness profile.
2. The corneal diagnostic instrument ofclaim 1 wherein at least one of the multiple slit lamp projectors comprises a flash lamp.
3. The corneal diagnostic instrument ofclaim 1 wherein at least one of the multiple slit lamp projectors comprises an optical fiber.
4. The corneal diagnostic instrument ofclaim 1 wherein at least one of the multiple slit lamp projectors comprises a CW light source.
5. The corneal diagnostic instrument ofclaim 1 wherein each of the multiple slit lamp projectors project a slit light beam at a substantially a predetermined constant angle with respect to a predetermined axis.
6. The corneal diagnostic instrument ofclaim 1 wherein each of the multiple slit lamp projectors projects a slit light beam with a uniform clocking angle separation from each other.
7. The corneal diagnostic instrument ofclaim 1 wherein at least one of the multiple slit lamp projectors projects a slit light beam having a white light spectrum.
8. The corneal diagnostic instrument ofclaim 1 wherein at least one of the multiple slit lamp projectors projects a slit light beam having an infrared spectrum.
9. The corneal diagnostic instrument ofclaim 1 wherein the multiple slit lamp projectors comprise 4 to 8 projectors.
10. The corneal diagnostic instrument ofclaim 1 wherein the controller comprises a synchronizer that causes the slit light beam images and the Placido ring image to be generated and detected in a predetermined sequence.
11. The corneal diagnostic instrument ofclaim 1 wherein the predetermined sequence causes the Placido ring image to be generated and detected before the slit light beam images are generated and detected.
12. The corneal diagnostic instrument ofclaim 1 wherein the predetermined sequence causes the Placido ring image to be generated and detected after the slit light beam images are generated and detected.
13. The corneal diagnostic instrument ofclaim 1 wherein:
the Placido ring image comprises radiation having first wavelengths and the slit light beam images comprise radiation having second wavelengths, wherein the first and second wavelengths are different; and
the camera system comprises a first camera that detects radiation having the first wavelengths and a second camera that detects radiation having the second wavelengths.
14. The corneal diagnostic instrument ofclaim 13 wherein:
the controller provides the predetermined sequence wherein the Placido ring image is generated and detected in the first camera during at least a portion of time that the slit light beam images are generated and detected in the second camera.
15. The corneal diagnostic instrument ofclaim 1 wherein the camera system comprises a movable lens.
16. A corneal diagnostic instrument that comprises:
a corneal topographer that determines a curvature profile of an anterior surface of a cornea;
multiple slit lamp projectors disposed to project slit light beams onto the cornea to generate slit light beam images;
a camera system optically disposed to detect the slit light beam images; and
a controller, coupled to the slit lamp projectors, the corneal topographer, and the camera system, to cause, in a predetermined sequence, (a) the slit light beam images to be generated and detected, and (b) the corneal topographer to obtain data used to determine the curvature profile, wherein the controller is responsive to the detected slit light beam images and the curvature profile to determine a corneal thickness profile.
17. The corneal diagnostic instrument ofclaim 16 wherein the corneal topographer generates a Placido ring image.
18. A method for corneal diagnosis that comprises steps of:
in a predetermined sequence, projecting radiation and multiple slit light beams onto a cornea to generate a Placido ring image and slit light beam images and detecting the Placido ring image and the slit light beam images; and
analyzing the Placido ring image and the slit light beam images to determine a corneal thickness profile.
19. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes generating the slit light beams utilizing at least one flash lamp.
20. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes generating the slit light beams utilizing at least one optical fiber.
21. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes generating the slit light beams utilizing at least one CW light source.
22. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes projecting the slit light beams at a substantially a predetermined constant angle with respect to a predetermined axis.
23. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes projecting the slit light beams with a uniform clocking angle separation one another.
24. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes projecting at least one slit light beam having a white light spectrum.
25. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes projecting at least one slit light beam having an infrared light spectrum.
26. The method ofclaim 18 wherein the step of projecting multiple slit light beams includes projecting 4 to 8 slit light beams.
27. A method for corneal diagnosis that comprise steps of:
utilizing a corneal topographer to obtain a curvature profile of an anterior surface of a cornea;
in a predetermined sequence, projecting multiple slit light beams from multiple projectors onto the cornea to generate slit light beam images and detecting the slit light beam images; and
analyzing the curvature profile and the slit light beam images to determine a corneal thickness profile.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/981,054US6575573B2 (en) | 2001-10-17 | 2001-10-17 | Method and apparatus for measuring a corneal profile of an eye |
| US10/051,192US6692126B1 (en) | 2001-10-17 | 2002-01-17 | Method and apparatus for measuring a corneal profile of an eye |
| PCT/EP2002/010970WO2003032823A2 (en) | 2001-10-17 | 2002-10-01 | Method and apparatus for measuring a corneal profile of an eye |
| JP2003535633AJP2005505372A (en) | 2001-10-17 | 2002-10-01 | Method and apparatus for measuring the corneal profile of the eye |
| EP02801299.5AEP1435832B1 (en) | 2001-10-17 | 2002-10-01 | Method and apparatus for measuring a corneal profile of an eye |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/981,054US6575573B2 (en) | 2001-10-17 | 2001-10-17 | Method and apparatus for measuring a corneal profile of an eye |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US10/051,192Continuation-In-PartUS6692126B1 (en) | 2001-10-17 | 2002-01-17 | Method and apparatus for measuring a corneal profile of an eye |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| US20030071968A1 US20030071968A1 (en) | 2003-04-17 |
| US6575573B2true US6575573B2 (en) | 2003-06-10 |
Family
ID=25528074
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US09/981,054Expired - Fee RelatedUS6575573B2 (en) | 2001-10-17 | 2001-10-17 | Method and apparatus for measuring a corneal profile of an eye |
| US10/051,192Expired - Fee RelatedUS6692126B1 (en) | 2001-10-17 | 2002-01-17 | Method and apparatus for measuring a corneal profile of an eye |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US10/051,192Expired - Fee RelatedUS6692126B1 (en) | 2001-10-17 | 2002-01-17 | Method and apparatus for measuring a corneal profile of an eye |
Country Status (1)
| Country | Link |
|---|---|
| US (2) | US6575573B2 (en) |
Cited By (37)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020163623A1 (en)* | 2001-04-18 | 2002-11-07 | Kabushiki Kaisha Topcon | Opthalmic characteristic measuring apparatus |
| US20030142270A1 (en)* | 2000-02-25 | 2003-07-31 | Almeida Jose Manuel Martins Borges De | System to measure the topography of both corneal surfaces and corneal thickness |
| US20050134797A1 (en)* | 2003-12-10 | 2005-06-23 | Grove Donald C. | Rapid switching slit scan image capture system |
| US20050174578A1 (en)* | 2004-02-10 | 2005-08-11 | Jay Wei | High efficiency low coherence interferometry |
| US20050203422A1 (en)* | 2004-02-10 | 2005-09-15 | Jay Wei | Optical apparatus and methods for performing eye examinations |
| US20080144035A1 (en)* | 2006-12-13 | 2008-06-19 | Allred Lloyd G | Optical calibration system and method |
| US20080151191A1 (en)* | 2006-12-26 | 2008-06-26 | Mcbeth Jeffrey B | Corneal Measurement Apparatus Having a Segmented Aperture and a Method of Using the Same |
| US20080212030A1 (en)* | 2006-12-21 | 2008-09-04 | Bentley Joseph R | Corneal measurement apparatus and a method of using the same |
| US20090157138A1 (en)* | 2006-04-18 | 2009-06-18 | Electrocore, Inc. | Methods And Apparatus For Treating Ileus Condition Using Electrical Signals |
| US20090161090A1 (en)* | 2007-06-27 | 2009-06-25 | Advanced Medical Optics, Inc. | Systems and Methods for Measuring the Shape and Location of an object |
| DE102008008732A1 (en) | 2008-02-11 | 2009-08-13 | Carl Zeiss Meditec Ag | Method and device for determining corneal radii |
| US20100110380A1 (en)* | 2008-11-05 | 2010-05-06 | Allred Lloyd G | Eye Measurement Apparatus and Methods of Using Same |
| US20100111381A1 (en)* | 2008-11-06 | 2010-05-06 | Mcbeth Jeffrey B | Methods and Apparatus for Facilitating Elimination of Ambient Light from an Image |
| US20100123873A1 (en)* | 2008-11-14 | 2010-05-20 | Amo Wavefront Sciences, Llc | Method of qualifying light spots for optical measurements and measurement instrument employing method of qualifying light spots |
| DE102008062745A1 (en) | 2008-12-17 | 2010-06-24 | Carl Zeiss Meditec Ag | Apparatus and method for determining the surface topography of an eye by evaluating the mirror images of symmetrical patterns |
| WO2011047076A1 (en)* | 2009-10-13 | 2011-04-21 | Acufocus, Inc. | Method and apparatus for centration of an ocular implant |
| US7976163B2 (en) | 2007-06-27 | 2011-07-12 | Amo Wavefront Sciences Llc | System and method for measuring corneal topography |
| DE102011102355A1 (en) | 2011-05-24 | 2012-11-29 | Carl Zeiss Meditec Ag | System for determining the topography of the cornea of an eye |
| DE102011102354A1 (en) | 2011-05-24 | 2012-11-29 | Carl Zeiss Meditec Ag | System for determining surface shape of cornea of eye, has keratoscope, illuminating unit, image recording unit with telecentric image capturing and control- and evaluation unit |
| US8585687B2 (en) | 2007-05-11 | 2013-11-19 | Amo Development, Llc | Combined wavefront and topography systems and methods |
| US8622546B2 (en) | 2011-06-08 | 2014-01-07 | Amo Wavefront Sciences, Llc | Method of locating valid light spots for optical measurement and optical measurement instrument employing method of locating valid light spots |
| DE102012019468A1 (en) | 2012-09-28 | 2014-04-03 | Carl Zeiss Meditec Ag | Device for determining cornea curvature of eye, has image recording unit and control and evaluation unit which is connected to illumination source and image pickup unit, so that telecentric aperture of swivel is varied |
| US8752958B2 (en) | 1999-03-01 | 2014-06-17 | Boston Innovative Optics, Inc. | System and method for increasing the depth of focus of the human eye |
| US8864824B2 (en) | 2003-06-17 | 2014-10-21 | Acufocus, Inc. | Method and apparatus for aligning a mask with the visual axis of an eye |
| US9005281B2 (en) | 2009-08-13 | 2015-04-14 | Acufocus, Inc. | Masked intraocular implants and lenses |
| US9138142B2 (en) | 2003-05-28 | 2015-09-22 | Acufocus, Inc. | Masked intraocular devices |
| US9204962B2 (en) | 2013-03-13 | 2015-12-08 | Acufocus, Inc. | In situ adjustable optical mask |
| DE102014210786A1 (en) | 2014-06-05 | 2015-12-17 | Carl Zeiss Meditec Ag | Topography module for ophthalmic devices with distance-independent keratometry measuring device and method for its use |
| DE102014210787A1 (en) | 2014-06-05 | 2015-12-17 | Carl Zeiss Meditec Ag | Distance-compensated measuring device for topographical and keratometric measurements on the eye |
| US9427311B2 (en) | 2009-08-13 | 2016-08-30 | Acufocus, Inc. | Corneal inlay with nutrient transport structures |
| US9427922B2 (en) | 2013-03-14 | 2016-08-30 | Acufocus, Inc. | Process for manufacturing an intraocular lens with an embedded mask |
| US9545303B2 (en) | 2011-12-02 | 2017-01-17 | Acufocus, Inc. | Ocular mask having selective spectral transmission |
| US9943403B2 (en) | 2014-11-19 | 2018-04-17 | Acufocus, Inc. | Fracturable mask for treating presbyopia |
| US10004593B2 (en) | 2009-08-13 | 2018-06-26 | Acufocus, Inc. | Intraocular lens with elastic mask |
| US10687935B2 (en) | 2015-10-05 | 2020-06-23 | Acufocus, Inc. | Methods of molding intraocular lenses |
| US11364110B2 (en) | 2018-05-09 | 2022-06-21 | Acufocus, Inc. | Intraocular implant with removable optic |
| US11464625B2 (en) | 2015-11-24 | 2022-10-11 | Acufocus, Inc. | Toric small aperture intraocular lens with extended depth of focus |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050043808A1 (en)* | 1994-05-06 | 2005-02-24 | Advanced Bio Surfaces, Inc. | Knee joint prosthesis |
| AU2002952772A0 (en)* | 2002-11-20 | 2002-12-05 | Clearmark Technologies Pty Ltd | A corneal topographer |
| EP1430829B1 (en)* | 2002-12-16 | 2008-04-09 | SIS AG Surgical Instrument Systems | Ophthalmic device and measuring method |
| DE20313745U1 (en)* | 2003-09-02 | 2003-11-20 | Oculus Optikgeräte GmbH, 35582 Wetzlar | Ophthalmological analysis system |
| SI21782A (en)* | 2004-06-04 | 2005-12-31 | Optotek D.O.O. | Slot lamp with white or colour adjustable led |
| CN101262811A (en)* | 2004-09-29 | 2008-09-10 | 保泽体艾D有限公司 | Corneal bioassay |
| US9004689B2 (en)* | 2008-04-17 | 2015-04-14 | Vereniging Vu-Windesheim | Apparatus for corneal shape analysis and method for determining a corneal thickness |
| US9743832B2 (en) | 2008-04-17 | 2017-08-29 | Cassini B.V. | Apparatus for corneal shape analysis and method for determining a corneal thickness |
| JP5592665B2 (en)* | 2010-02-18 | 2014-09-17 | 株式会社トーメーコーポレーション | Corneal shape measuring method and corneal shape measuring device |
| JP2013031639A (en)* | 2011-07-01 | 2013-02-14 | Canon Inc | Ophthalmologic apparatus and ophthalmologic system |
| DE102011083789A1 (en)* | 2011-09-29 | 2013-04-04 | Oculus Optikgeräte GmbH | Ophthalmological analysis method |
| CN104720740B (en)* | 2015-04-02 | 2016-08-17 | 深圳市莫廷影像技术有限公司 | Utilize slit-lamp angle measurement film curvature distribution and the method for thickness distribution |
| NL2018712B1 (en) | 2017-04-13 | 2018-10-24 | Cassini B V | Eye measuring apparatus |
| CH714591A1 (en)* | 2018-01-25 | 2019-07-31 | Haag Ag Streit | Eye examination apparatus and method for determining image data. |
| US11564563B2 (en) | 2018-02-17 | 2023-01-31 | Aizhong Zhang | Apparatus and method of a multifunctional ophthalmic instrument |
| JP7149519B2 (en)* | 2018-09-27 | 2022-10-07 | 国立大学法人 筑波大学 | Eye measurement device and method |
| CN111281338B (en)* | 2018-12-08 | 2022-08-26 | 广东英华投资控股有限公司 | Slit-lamp microscope tester |
| US11253151B2 (en) | 2019-09-08 | 2022-02-22 | Aizhong Zhang | Multispectral and hyperspectral ocular surface evaluator |
| WO2022019751A1 (en)* | 2020-07-21 | 2022-01-27 | Paul Phillip Van Saarloos | Reflection based corneal topography system using prisms for improved accuracy and method of use |
| EP4287928A1 (en)* | 2021-02-08 | 2023-12-13 | Alcon Inc. | Multi-view corneal topographer |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4420228A (en) | 1980-06-12 | 1983-12-13 | Humphrey Instruments, Inc. | Method and apparatus for analysis of corneal shape |
| US4978213A (en) | 1987-08-26 | 1990-12-18 | El Hage Sami G | Apparatus for determining the contour of the cornea of a human eye |
| US5307097A (en) | 1992-11-05 | 1994-04-26 | Kera-Metrics, Inc. | Corneal topography system including single-direction shearing of holograph grating in orthogonal directions |
| US5404884A (en) | 1990-10-26 | 1995-04-11 | Lempert; Philip | Method and apparatus for imaging and analysis of corneal tissue |
| US5475452A (en) | 1994-02-24 | 1995-12-12 | Keravision, Inc. | Device and method for mapping objects |
| US5512966A (en) | 1993-06-24 | 1996-04-30 | Orbtek, Inc. | Ophthalmic pachymeter and method of making ophthalmic determinations |
| US5539837A (en) | 1992-04-29 | 1996-07-23 | Lindmark; Richard C. | Apparatus and method for measuring curved surfaces |
| US5663781A (en) | 1988-06-29 | 1997-09-02 | G. Rodenstock Instrumente Gmbh | Apparatus for the examination of objects and the determination of topography |
| US5847804A (en) | 1994-10-28 | 1998-12-08 | Eyesys Technologies, Inc. | Multi-camera corneal analysis system |
| US5861955A (en) | 1994-04-25 | 1999-01-19 | Medjet Inc. | Topographical cornea mapping for corneal vision correction |
| US5870167A (en) | 1993-07-14 | 1999-02-09 | Knopp; Carl F. | Apparatus and method for imaging anterior structures of the eye |
| US6099522A (en)* | 1989-02-06 | 2000-08-08 | Visx Inc. | Automated laser workstation for high precision surgical and industrial interventions |
| US6234631B1 (en) | 2000-03-09 | 2001-05-22 | Lasersight Technologies, Inc. | Combination advanced corneal topography/wave front aberration measurement |
Family Cites Families (58)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3248162A (en) | 1966-04-26 | Photokera ixoscolxe wit with reflecting ringsin cylindrigal cage structure | ||
| US2174308A (en) | 1937-01-11 | 1939-09-26 | Zeiss Carl Fa | Ophthalmometer |
| FR1211981A (en) | 1958-12-26 | 1960-03-21 | Ophthalmometer | |
| US3486812A (en) | 1966-09-14 | 1969-12-30 | David Volk | Apparatus for measuring the eccentricity of an approximately conicoid surface |
| US3536384A (en) | 1968-07-05 | 1970-10-27 | Battelle Development Corp | Apparatus for determining corneal curvature and the like |
| US3598478A (en) | 1968-11-26 | 1971-08-10 | Plastic Contact Lens Co | Apparatus for determining cornea contour |
| US3634003A (en) | 1970-01-02 | 1972-01-11 | David Guyton | Optical system for imaging scheiner apertures in an optometer |
| US3609017A (en) | 1970-05-21 | 1971-09-28 | Benjamin Nuchman | Means for extending the range of keratometers |
| USRE27475E (en) | 1971-02-08 | 1972-09-05 | Method for measurement of the shape and curvature of a cornea | |
| US3797921A (en) | 1972-06-05 | 1974-03-19 | Temco Mfg Co | Photographing apparatus for determining corneal radius |
| JPS5714803Y2 (en) | 1973-05-22 | 1982-03-27 | ||
| US3895860A (en) | 1974-04-08 | 1975-07-22 | Jessen Inc Wesley | Method for comparing corneal measurements |
| US4019813A (en) | 1976-01-19 | 1977-04-26 | Baylor College Of Medicine | Optical apparatus for obtaining measurements of portions of the eye |
| DE2641004C2 (en) | 1976-09-11 | 1981-12-17 | Battelle-Institut E.V., 6000 Frankfurt | Device for measuring the corneal curvature |
| DE2643344A1 (en) | 1976-09-25 | 1978-03-30 | Zeiss Carl Fa | DEVICE FOR DETERMINING CORNEAL TASTIGMATISM IN THE HUMAN EYE |
| US4157859A (en) | 1977-05-26 | 1979-06-12 | Clifford Terry | Surgical microscope system |
| DE2905915C3 (en) | 1979-02-16 | 1981-11-26 | Fa. Carl Zeiss, 7920 Heidenheim | Combination device for eye examination |
| US4256385A (en) | 1979-02-22 | 1981-03-17 | Velotron Machine Corp. | Cornea-examining instrument |
| DE3000995C2 (en) | 1980-01-12 | 1982-06-16 | Fa. Carl Zeiss, 7920 Heidenheim | Distance-independent, high-accuracy ophthalmometer |
| US4426141A (en) | 1981-04-23 | 1984-01-17 | Holcomb Harry F | Bright ring keratoscope |
| US4491398A (en) | 1981-11-30 | 1985-01-01 | Surgidev Corporation | Hand-held keratometer |
| US4490022A (en) | 1982-01-04 | 1984-12-25 | Reynolds Alvin E | Apparatus for corneal corrective techniques |
| US4569576A (en) | 1982-08-31 | 1986-02-11 | Moskovsky Nauchno-Issledovatelsky Institut Glaznykh Boleznei Imeni Gelmgoltsa | Method and device for determining cornea surface topography |
| US4597648A (en) | 1983-04-01 | 1986-07-01 | Keratometer Research And Development | Keratometer |
| US4685140A (en) | 1984-06-26 | 1987-08-04 | Kera Corporation | Keratograph autoscanner system |
| US4764006A (en) | 1985-09-13 | 1988-08-16 | Canon Kabushiki Kaisha | Ophthalmic measuring apparatus |
| US4799784A (en) | 1986-06-23 | 1989-01-24 | Aran Safir | Visual vertex finder |
| US4772115A (en) | 1986-09-02 | 1988-09-20 | Computed Anatomy Incorporated | Illuminated ring keratometer device |
| US4834529A (en) | 1986-11-03 | 1989-05-30 | Barrett Graham D | Apparatus and method for determining the symmetry of a surface |
| US4779973A (en) | 1986-11-06 | 1988-10-25 | David Miller | Photokeratometric device |
| US5227818A (en) | 1987-08-26 | 1993-07-13 | El Hage Sami G | Apparatus for determining the contour of the cornea of a human eye |
| US4863260A (en) | 1987-11-04 | 1989-09-05 | Computed Anatomy Inc. | System for topographical modeling of anatomical surfaces |
| US5106183A (en) | 1987-11-25 | 1992-04-21 | Taunton Technologies, Inc. | Topography measuring apparatus |
| US4998819A (en) | 1987-11-25 | 1991-03-12 | Taunton Technologies, Inc. | Topography measuring apparatus |
| EP0374306A1 (en) | 1988-12-23 | 1990-06-27 | Herman Van Gelderen | Apparatus and method for determining contact lenses |
| US4995716A (en) | 1989-03-09 | 1991-02-26 | Par Technology Corporation | Method and apparatus for obtaining the topography of an object |
| US5159361A (en) | 1989-03-09 | 1992-10-27 | Par Technology Corporation | Method and apparatus for obtaining the topography of an object |
| US5018850A (en) | 1990-03-13 | 1991-05-28 | Computed Anatomy Incorporated | Illuminated ring device |
| CA2081377C (en) | 1990-03-13 | 1999-05-04 | Martin Gersten | Compact keratoscope with interchangeable cones |
| US5009498A (en) | 1990-03-20 | 1991-04-23 | Computed Anatomy Inc. | Interchangeable keratoscope device |
| JPH04332525A (en) | 1991-05-02 | 1992-11-19 | Topcon Corp | Cornea shape measuring instrument |
| US5194882A (en) | 1991-06-03 | 1993-03-16 | General Electric Company | Keratographic instrument using holographic placido illuminator to reduce alignment sensitivity |
| US5214456A (en) | 1991-10-09 | 1993-05-25 | Computed Anatomy Incorporated | Mapping of corneal topography with display of pupil perimeter |
| US5384608A (en) | 1991-10-10 | 1995-01-24 | Computed Anatomy Inc. | Method for displaying corneal topography |
| US5585873A (en) | 1991-10-11 | 1996-12-17 | Alcon Laboratories, Inc. | Automated hand-held keratometer |
| NL9200071A (en) | 1992-01-15 | 1993-08-02 | Stichting Science Park Maastri | DEVICE FOR DETERMINING THE TOPOGRAPHY OF A CURVED SURFACE. |
| JP3420597B2 (en) | 1992-06-30 | 2003-06-23 | 株式会社ニデック | Anterior segment imaging device |
| JPH0630900A (en) | 1992-07-13 | 1994-02-08 | Kimiya Shimizu | Display method for optical characteristic of cornea |
| US5349398A (en) | 1992-07-17 | 1994-09-20 | The Trustees Of Columbia University In The City Of New York | Ophthalmometer system |
| US5891131A (en) | 1993-02-01 | 1999-04-06 | Arizona Board Of Regents | Method and apparatus for automated simulation and design of corneal refractive procedures |
| US5418714A (en) | 1993-04-08 | 1995-05-23 | Eyesys Laboratories, Inc. | Method and apparatus for variable block size interpolative coding of images |
| US5418582A (en) | 1993-10-15 | 1995-05-23 | Lions Eye Institute Perth | Photokeratoscope apparatus and method |
| US5412441A (en) | 1994-03-07 | 1995-05-02 | Tibbling; Lars | Keratometer device having photographically produced bore pattern |
| US5865742A (en) | 1995-03-06 | 1999-02-02 | Massie Research Laboratories, Inc. | Non-contact tonometer |
| US6079831A (en) | 1997-04-24 | 2000-06-27 | Orbtek, Inc. | Device and method for mapping the topography of an eye using elevation measurements in combination with slope measurements |
| JP3848492B2 (en)* | 1998-09-04 | 2006-11-22 | 株式会社ニデック | Cornea surgery device |
| DE69906779T2 (en)* | 1998-11-13 | 2004-01-29 | Jean Benedikt | METHOD AND DEVICE FOR SIMULTANEOUS DETECTION OF SURFACE OPOGRAPHY AND BIOMETRY OF AN EYE |
| JP3798199B2 (en)* | 1999-09-29 | 2006-07-19 | 株式会社ニデック | Ophthalmic equipment |
- 2001
- 2001-10-17USUS09/981,054patent/US6575573B2/ennot_activeExpired - Fee Related
- 2002
- 2002-01-17USUS10/051,192patent/US6692126B1/ennot_activeExpired - Fee Related
Patent Citations (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4420228A (en) | 1980-06-12 | 1983-12-13 | Humphrey Instruments, Inc. | Method and apparatus for analysis of corneal shape |
| US4978213A (en) | 1987-08-26 | 1990-12-18 | El Hage Sami G | Apparatus for determining the contour of the cornea of a human eye |
| US4978213B1 (en) | 1987-08-26 | 1997-03-11 | Alcon Lab Inc | Apparatus for determining the contour of the cornea of a human eye |
| US5663781A (en) | 1988-06-29 | 1997-09-02 | G. Rodenstock Instrumente Gmbh | Apparatus for the examination of objects and the determination of topography |
| US6099522A (en)* | 1989-02-06 | 2000-08-08 | Visx Inc. | Automated laser workstation for high precision surgical and industrial interventions |
| US5404884A (en) | 1990-10-26 | 1995-04-11 | Lempert; Philip | Method and apparatus for imaging and analysis of corneal tissue |
| US5539837A (en) | 1992-04-29 | 1996-07-23 | Lindmark; Richard C. | Apparatus and method for measuring curved surfaces |
| US5838811A (en) | 1992-04-29 | 1998-11-17 | Lindmark; Richard C. | System for measuring curved surfaces |
| US5307097A (en) | 1992-11-05 | 1994-04-26 | Kera-Metrics, Inc. | Corneal topography system including single-direction shearing of holograph grating in orthogonal directions |
| US5512966A (en) | 1993-06-24 | 1996-04-30 | Orbtek, Inc. | Ophthalmic pachymeter and method of making ophthalmic determinations |
| US5512965A (en) | 1993-06-24 | 1996-04-30 | Orbtek, Inc. | Ophthalmic instrument and method of making ophthalmic determinations using Scheimpflug corrections |
| US5870167A (en) | 1993-07-14 | 1999-02-09 | Knopp; Carl F. | Apparatus and method for imaging anterior structures of the eye |
| US5592246A (en) | 1994-02-24 | 1997-01-07 | Keravision, Inc. | Device and method for mapping objects |
| US5475452A (en) | 1994-02-24 | 1995-12-12 | Keravision, Inc. | Device and method for mapping objects |
| US5861955A (en) | 1994-04-25 | 1999-01-19 | Medjet Inc. | Topographical cornea mapping for corneal vision correction |
| US5847804A (en) | 1994-10-28 | 1998-12-08 | Eyesys Technologies, Inc. | Multi-camera corneal analysis system |
| US6234631B1 (en) | 2000-03-09 | 2001-05-22 | Lasersight Technologies, Inc. | Combination advanced corneal topography/wave front aberration measurement |
Cited By (70)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8752958B2 (en) | 1999-03-01 | 2014-06-17 | Boston Innovative Optics, Inc. | System and method for increasing the depth of focus of the human eye |
| US20030142270A1 (en)* | 2000-02-25 | 2003-07-31 | Almeida Jose Manuel Martins Borges De | System to measure the topography of both corneal surfaces and corneal thickness |
| US6913358B2 (en)* | 2000-02-25 | 2005-07-05 | Universidade Do Minho | System of measure the topography of both corneal surfaces and corneal thickness |
| US6685320B2 (en)* | 2001-04-18 | 2004-02-03 | Kabushiki Kaisha Topcon | Opthalmic characteristic measuring apparatus |
| US20020163623A1 (en)* | 2001-04-18 | 2002-11-07 | Kabushiki Kaisha Topcon | Opthalmic characteristic measuring apparatus |
| US10869752B2 (en) | 2003-05-28 | 2020-12-22 | Acufocus, Inc. | Mask for increasing depth of focus |
| US9138142B2 (en) | 2003-05-28 | 2015-09-22 | Acufocus, Inc. | Masked intraocular devices |
| US8864824B2 (en) | 2003-06-17 | 2014-10-21 | Acufocus, Inc. | Method and apparatus for aligning a mask with the visual axis of an eye |
| US7347549B2 (en)* | 2003-12-10 | 2008-03-25 | Bausch & Lomb Incorporated | Rapid switching slit scan image capture system |
| US20050134797A1 (en)* | 2003-12-10 | 2005-06-23 | Grove Donald C. | Rapid switching slit scan image capture system |
| US7280221B2 (en) | 2004-02-10 | 2007-10-09 | Optovue, Inc. | High efficiency low coherence interferometry |
| US20050203422A1 (en)* | 2004-02-10 | 2005-09-15 | Jay Wei | Optical apparatus and methods for performing eye examinations |
| US20050174578A1 (en)* | 2004-02-10 | 2005-08-11 | Jay Wei | High efficiency low coherence interferometry |
| US7631970B2 (en) | 2004-02-10 | 2009-12-15 | Carl Zeiss Meditec, Inc. | Optical apparatus and methods for performing eye examinations |
| US20090157138A1 (en)* | 2006-04-18 | 2009-06-18 | Electrocore, Inc. | Methods And Apparatus For Treating Ileus Condition Using Electrical Signals |
| US20080144035A1 (en)* | 2006-12-13 | 2008-06-19 | Allred Lloyd G | Optical calibration system and method |
| US7859677B2 (en) | 2006-12-13 | 2010-12-28 | Bausch & Lomb Incorporated | Optical calibration system and method |
| US20080212030A1 (en)* | 2006-12-21 | 2008-09-04 | Bentley Joseph R | Corneal measurement apparatus and a method of using the same |
| US7648241B2 (en) | 2006-12-21 | 2010-01-19 | Bausch & Lamb Incorporated | Corneal measurement apparatus and a method of using the same |
| US7896497B2 (en) | 2006-12-26 | 2011-03-01 | Bausch & Lomb Incorporated | Corneal measurement apparatus having a segmented aperture and a method of using the same |
| US20080151191A1 (en)* | 2006-12-26 | 2008-06-26 | Mcbeth Jeffrey B | Corneal Measurement Apparatus Having a Segmented Aperture and a Method of Using the Same |
| US8585687B2 (en) | 2007-05-11 | 2013-11-19 | Amo Development, Llc | Combined wavefront and topography systems and methods |
| US7988290B2 (en) | 2007-06-27 | 2011-08-02 | AMO Wavefront Sciences LLC. | Systems and methods for measuring the shape and location of an object |
| US7976163B2 (en) | 2007-06-27 | 2011-07-12 | Amo Wavefront Sciences Llc | System and method for measuring corneal topography |
| US20090161090A1 (en)* | 2007-06-27 | 2009-06-25 | Advanced Medical Optics, Inc. | Systems and Methods for Measuring the Shape and Location of an object |
| DE102008008732A1 (en) | 2008-02-11 | 2009-08-13 | Carl Zeiss Meditec Ag | Method and device for determining corneal radii |
| US20100110380A1 (en)* | 2008-11-05 | 2010-05-06 | Allred Lloyd G | Eye Measurement Apparatus and Methods of Using Same |
| US8092024B2 (en) | 2008-11-05 | 2012-01-10 | Bausch & Lomb Incorporated | Eye measurement apparatus and methods of using same |
| US20100111381A1 (en)* | 2008-11-06 | 2010-05-06 | Mcbeth Jeffrey B | Methods and Apparatus for Facilitating Elimination of Ambient Light from an Image |
| US8295635B2 (en) | 2008-11-06 | 2012-10-23 | Bausch & Lomb Incorporated | Methods and apparatus for facilitating elimination of ambient light from an image |
| US7988293B2 (en) | 2008-11-14 | 2011-08-02 | AMO Wavefront Sciences LLC. | Method of qualifying light spots for optical measurements and measurement instrument employing method of qualifying light spots |
| US20100123873A1 (en)* | 2008-11-14 | 2010-05-20 | Amo Wavefront Sciences, Llc | Method of qualifying light spots for optical measurements and measurement instrument employing method of qualifying light spots |
| DE102008062745A1 (en) | 2008-12-17 | 2010-06-24 | Carl Zeiss Meditec Ag | Apparatus and method for determining the surface topography of an eye by evaluating the mirror images of symmetrical patterns |
| US10548717B2 (en) | 2009-08-13 | 2020-02-04 | Acufocus, Inc. | Intraocular lens with elastic mask |
| US11357617B2 (en) | 2009-08-13 | 2022-06-14 | Acufocus, Inc. | Method of implanting and forming masked intraocular implants and lenses |
| US9005281B2 (en) | 2009-08-13 | 2015-04-14 | Acufocus, Inc. | Masked intraocular implants and lenses |
| US10004593B2 (en) | 2009-08-13 | 2018-06-26 | Acufocus, Inc. | Intraocular lens with elastic mask |
| US11311371B2 (en) | 2009-08-13 | 2022-04-26 | Acufocus, Inc. | Intraocular lens with elastic mask |
| US9427311B2 (en) | 2009-08-13 | 2016-08-30 | Acufocus, Inc. | Corneal inlay with nutrient transport structures |
| US10449036B2 (en) | 2009-08-13 | 2019-10-22 | Acufocus, Inc. | Masked intraocular implants and lenses |
| US9492272B2 (en) | 2009-08-13 | 2016-11-15 | Acufocus, Inc. | Masked intraocular implants and lenses |
| WO2011047076A1 (en)* | 2009-10-13 | 2011-04-21 | Acufocus, Inc. | Method and apparatus for centration of an ocular implant |
| WO2012160049A1 (en) | 2011-05-24 | 2012-11-29 | Carl Zeiss Meditec Ag | System for determining the topography of the cornea of an eye |
| DE102011102354A1 (en) | 2011-05-24 | 2012-11-29 | Carl Zeiss Meditec Ag | System for determining surface shape of cornea of eye, has keratoscope, illuminating unit, image recording unit with telecentric image capturing and control- and evaluation unit |
| US9084564B2 (en) | 2011-05-24 | 2015-07-21 | Carl Zeiss Meditec Ag | System for determining the topography of the cornea of an eye |
| DE102011102355A1 (en) | 2011-05-24 | 2012-11-29 | Carl Zeiss Meditec Ag | System for determining the topography of the cornea of an eye |
| US8622546B2 (en) | 2011-06-08 | 2014-01-07 | Amo Wavefront Sciences, Llc | Method of locating valid light spots for optical measurement and optical measurement instrument employing method of locating valid light spots |
| US10765508B2 (en) | 2011-12-02 | 2020-09-08 | AcFocus, Inc. | Ocular mask having selective spectral transmission |
| US9848979B2 (en) | 2011-12-02 | 2017-12-26 | Acufocus, Inc. | Ocular mask having selective spectral transmission |
| US9545303B2 (en) | 2011-12-02 | 2017-01-17 | Acufocus, Inc. | Ocular mask having selective spectral transmission |
| US10342656B2 (en) | 2011-12-02 | 2019-07-09 | Acufocus, Inc. | Ocular mask having selective spectral transmission |
| DE102012019468A1 (en) | 2012-09-28 | 2014-04-03 | Carl Zeiss Meditec Ag | Device for determining cornea curvature of eye, has image recording unit and control and evaluation unit which is connected to illumination source and image pickup unit, so that telecentric aperture of swivel is varied |
| US9603704B2 (en) | 2013-03-13 | 2017-03-28 | Acufocus, Inc. | In situ adjustable optical mask |
| US11771552B2 (en) | 2013-03-13 | 2023-10-03 | Acufocus, Inc. | In situ adjustable optical mask |
| US9204962B2 (en) | 2013-03-13 | 2015-12-08 | Acufocus, Inc. | In situ adjustable optical mask |
| US10939995B2 (en) | 2013-03-13 | 2021-03-09 | Acufocus, Inc. | In situ adjustable optical mask |
| US10350058B2 (en) | 2013-03-13 | 2019-07-16 | Acufocus, Inc. | In situ adjustable optical mask |
| US9427922B2 (en) | 2013-03-14 | 2016-08-30 | Acufocus, Inc. | Process for manufacturing an intraocular lens with an embedded mask |
| US10583619B2 (en) | 2013-03-14 | 2020-03-10 | Acufocus, Inc. | Process for manufacturing an intraocular lens with an embedded mask |
| US9573328B2 (en) | 2013-03-14 | 2017-02-21 | Acufocus, Inc. | Process for manufacturing an intraocular lens with an embedded mask |
| US10183453B2 (en) | 2013-03-14 | 2019-01-22 | Acufocus, Inc. | Process for manufacturing an intraocular lens with an embedded mask |
| US9844919B2 (en) | 2013-03-14 | 2017-12-19 | Acufocus, Inc. | Process for manufacturing an intraocular lens with an embedded mask |
| DE102014210787A1 (en) | 2014-06-05 | 2015-12-17 | Carl Zeiss Meditec Ag | Distance-compensated measuring device for topographical and keratometric measurements on the eye |
| DE102014210786A1 (en) | 2014-06-05 | 2015-12-17 | Carl Zeiss Meditec Ag | Topography module for ophthalmic devices with distance-independent keratometry measuring device and method for its use |
| US10213103B2 (en) | 2014-06-05 | 2019-02-26 | Carl Zeiss Meditec Ag | Topography module for ophthalmological devices with a distance-independent keratometer and method for the use thereof |
| US9943403B2 (en) | 2014-11-19 | 2018-04-17 | Acufocus, Inc. | Fracturable mask for treating presbyopia |
| US10687935B2 (en) | 2015-10-05 | 2020-06-23 | Acufocus, Inc. | Methods of molding intraocular lenses |
| US11690707B2 (en) | 2015-10-05 | 2023-07-04 | Acufocus, Inc. | Methods of molding intraocular lenses |
| US11464625B2 (en) | 2015-11-24 | 2022-10-11 | Acufocus, Inc. | Toric small aperture intraocular lens with extended depth of focus |
| US11364110B2 (en) | 2018-05-09 | 2022-06-21 | Acufocus, Inc. | Intraocular implant with removable optic |
Also Published As
| Publication number | Publication date |
|---|---|
| US20030071968A1 (en) | 2003-04-17 |
| US6692126B1 (en) | 2004-02-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6575573B2 (en) | Method and apparatus for measuring a corneal profile of an eye | |
| US7980696B1 (en) | Ophthalmic photographing apparatus | |
| JP2942321B2 (en) | Transillumination imaging equipment | |
| JP3420597B2 (en) | Anterior segment imaging device | |
| US20150272434A1 (en) | Fundus photography device | |
| EP1391176A1 (en) | Method and arrangement for performing measurements of the topography of a corneal surface | |
| JP2649088B2 (en) | Positioning device for ophthalmic examination instruments | |
| US9687143B2 (en) | Ophthalmic photography device, ophthalmic photography method, and ophthalmic photography program | |
| EP1435832B1 (en) | Method and apparatus for measuring a corneal profile of an eye | |
| JP3576656B2 (en) | Alignment detection device for ophthalmic instruments | |
| JP7178683B2 (en) | ophthalmic equipment | |
| JPH0430854B2 (en) | ||
| JPH11235316A (en) | Optometrical device | |
| JP2983236B2 (en) | Corneal laser surgery device | |
| JP3187083B2 (en) | Optometry device | |
| JP3004653B2 (en) | Ophthalmic equipment | |
| JPH03500136A (en) | Device for generating images of objects (1) | |
| JP2707337B2 (en) | Corneal shape measuring device | |
| JP3257823B2 (en) | Ophthalmic equipment | |
| JP2001231753A (en) | Opthalmometer | |
| JPH0315438A (en) | Alignment device for fundus camera | |
| JP3581454B2 (en) | Corneal endothelial imaging device with corneal thickness measurement function | |
| JP3106127B2 (en) | Ophthalmic equipment | |
| JP3056799B2 (en) | Ophthalmic equipment | |
| WO2025079384A1 (en) | Ophthalmologic device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment | Owner name:CARL ZEISS OPHTHALMIC SYSTEMS, INC., CALIFORNIA Free format text:ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LAI, MING;XIE, JING-GANG;WEI, JAY;REEL/FRAME:012277/0173 Effective date:20011016 | |
| AS | Assignment | Owner name:CARL ZEISS MEDITEC, INC., CALIFORNIA Free format text:CHANGE OF NAME;ASSIGNOR:CARL ZEISS OPHTHALMIC SYSTEMS, INC.;REEL/FRAME:014546/0236 Effective date:20020712 | |
| FPAY | Fee payment | Year of fee payment:4 | |
| REMI | Maintenance fee reminder mailed | ||
| LAPS | Lapse for failure to pay maintenance fees | ||
| STCH | Information on status: patent discontinuation | Free format text:PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 | |
| FP | Lapsed due to failure to pay maintenance fee | Effective date:20110610 |